Astronomy Blog http://www.strudel.org.uk/blog/astro/ An astronomy blog usually (but not always) based in the UK. Pondering questions such as What is in an exoplanet name ?. en-gb Thu, 26 Aug 2010 12:35:00 +0100 Thu, 26 Aug 2010 12:35:00 +0100 http://blogs.law.harvard.edu/tech/rss Marzipan (v0.6.2) Astromovies http://www.strudel.org.uk/blog/astro/000945.shtml @adam_avison started the astronomy-themed hashtag #astromovies. The idea was to think of astronomical versions of movie titles and it has got pretty popular. I thought I'd share some of those that I liked.
- taken from Astronomy Blog (www.strudel.org.uk/blog/astro/)]]> Thu, 26 Aug 2010 12:35:00 +0100 http://www.strudel.org.uk/blog/astro/000945.shtml AVM with Javascript http://www.strudel.org.uk/blog/astro/000944.shtml mentioned Astronomy Visualization Metadata before as well as my attempts to make a microformat and include the object categories in LookUP results. It is an attempt to add useful astronomical information to astronomical image files ("pretty pictures") used on the web so that when someone downloads an astronomical image the information such as position, object name, observing frequencies etc go with it (unless it gets edited).

Recently, I've been thinking about the possibility of placing pretty pictures in Chromoscope. This is already possible in the WorldWideTelescope plug-in but getting it to work in a normal browser requires a bit of effort. The idea isn't fully fledged yet but, to make it even tennable, I had to be able to extract the metadata from the image within the web-browser.

A few weeks ago I discovered a nice Javascript library that reads EXIF information from images. This was a good start but I soon discovered that it didn't read the AVM data as it isn't stored in the same way as the EXIF information. After a bit of head scratching, and reading the Adobe XMP specifications, I was able to adapt the EXIF Javascript library to read AVM data too. I've created a test page with a few images on it to check that it works. Thanks to @kimberlykowal for helping check the Chandra image. - taken from Astronomy Blog (www.strudel.org.uk/blog/astro/)]]> Tue, 24 Aug 2010 19:28:00 +0100 http://www.strudel.org.uk/blog/astro/000944.shtml Astronomer H-R diagram http://www.strudel.org.uk/blog/astro/000943.shtml Hertzsprung-Russell diagram. It was developed to show the relationships between the temperature (or colour) of a star and its luminosity. The other week I saw a tweet referring to someone as an "astronomy media star". This interesting stellar classification got me thinking about an alternative version of the H-R diagram. In my alternate reality I imagined a version classifying astronomers* and so, after a little consultation with other astronomers (thanks Sarah, Tess, Mike, Paul and Amanda) and some free time**, I present...
Click to embiggen. Apologies to Hertzsprung and Russell. If you are one of the names on this plot and you feel your numbers are very wrong, let me know and I'll update it. CREDIT: Stuart
This isn't in any way supposed to be accurate - it is qualitative - and most of the "Main Career Sequence" is invented based on expectations of an evolutionary sequence assuming little use of the internet before becoming an astronomer. Mega-stars such as Dr Brian May may follow a totally different path. Of course, not all astronomers make it along the main sequence and many go off to other jobs through either an "academia runaway" or a "funding instability crisis". The "dark astronomers" (we have dark matter and dark energy so why not?) are theorised to exist but haven't been directly detected so if you have evidence for one, please let me know.

For those wanting technical details, the data for the red stars comes from NASA's ADS/SPIRES-HEP (limited to peer review) and searching for the person's name (in quotation marks) on Google. Both numbers are affected by name-sake contamination and the Google-dance/search customisation adds to the uncertainty on the y-axis. Update 2010-07-22T11:10:00 UT: It turns out that Google gives wildly different results depending on which Google you are connected to. Being in the UK I was automatically redirected to google.co.uk and that is where these numbers come from. Google.com seems to produce more search results. I may re-make this plot using Google.com as the standard.

If anyone has the time to properly classify a few hundred astronomers you are welcome to do that and send me the data!

* I know Brian Cox is technically a particle physicist but he is the Sun Professor which makes him almost a solar physicist ;-)
** Internet-based diversions such as this usually result in people saying "he has too much free time". That is not entirely inaccurate. - taken from Astronomy Blog (www.strudel.org.uk/blog/astro/)]]> Wed, 21 Jul 2010 12:36:00 +0100 http://www.strudel.org.uk/blog/astro/000943.shtml Planck All-sky http://www.strudel.org.uk/blog/astro/000942.shtml European Space Agency and the Planck Consortium released the Planck satellite's first view of the entire sky. Behold.

Planck sky
A false-colour image of the whole sky as seen by Planck. The dust throughout the Galaxy is shown in blue. In the background, the mottled yellow features are relic radiation, called the Cosmic Microwave Background, which contains information about the earliest stages of the Universe. This image is a low-resolution version of the full data set. CREDIT: ESA, Planck LFI and HFI Consortia (2010)
Planck was launched on May 14th 2009 and, after three months of travelling and instrument testing, started taking science data in August last year. Early on we were treated to first light images, an image of cold dust around the Galactic Centre, and patches of the sky near Orion and Perseus. Now, for the first time, we get to see a view of the entire sky as seen by Planck.

Planck's main task is to study the echoes of the Big Bang; the cosmic microwave background (CMB) radiation. It builds on the successes of COBE and WMAP that have gone before but covers a much bigger range of frequencies (30-857 GHz) and will ultimately be more sensitive. The range of frequencies is very important as it helps to disentangle the many sources of microwave radiation in the Universe that detract from the cosmological signal that Planck is trying to observe.

Today's image may vaguely resemble the Flying Spaghetti Monster* but actually shows our galaxy - the Milky Way - across the middle and you can see streamers of cold gas and dust in our local neighbourhood (local means within a few hundred light years) stretching above and below it. To get your bearings, there is an annotated version and you can also explore it in Chromoscope! Near the top and bottom of the image you'll see a mottled pattern. That is a glimpse of the CMB; the remains of the fireball out of which our Universe sprang into existence 13.7 billion years ago.

This image is only the start of the amazing data that is to come from Planck. Planck is imaging the entire sky every 8 months or so and that means it produces lots of data. There is plenty of work ahead, and at least two full surveys of the sky are required to fully calibrate everything, so the first cosmological science isn't expected until 2012. In a couple of years, we should expect to see a much better and higher resolution view of the Universe. Meanwhile, my congratulations to all the people that have worked on Planck over the past 20 years. The hard work was certainly worth it.

* It doesn't help that the filename contains "FSM" (which actually stands for "full-sky map"). - taken from Astronomy Blog (www.strudel.org.uk/blog/astro/)]]> Mon, 05 Jul 2010 09:05:00 +0100 http://www.strudel.org.uk/blog/astro/000942.shtml LookUP blog posts http://www.strudel.org.uk/blog/astro/000941.shtml LookUP. First, the change. I realised that the images I was using from Flickr included copyright images so I've limited the search to those with licenses that allow them to be included in the LookUP results. Unfortunately, that does reduce the number of images and removes quite a few of the nice astrophotography shots. If you have a Flickr account and astro photographs, please consider using a permissable license and using astrotags.

While getting my head around astrotags I remembered another project I created that made use of tags on blog posts. I realised that I could make use of SpaceBuzz to add a list of blog posts about the object. Of course this relies on bloggers tagging their posts. If you blog about astronomy, make sure you tag your posts with the name of any astronomical objects you mention and then you'll appear in the LookUP results. Here is an example for Titan.

With all the cross-links I now have between Chromoscope, SpaceBuzz and LookUP, it's almost as if I created them with a plan. - taken from Astronomy Blog (www.strudel.org.uk/blog/astro/)]]> Wed, 30 Jun 2010 11:43:00 +0100 http://www.strudel.org.uk/blog/astro/000941.shtml LookUP, Images and Astrotags http://www.strudel.org.uk/blog/astro/000940.shtml I created LookUP a while back to make it easy to find out the positions of any astronomical object. In the background LookUP goes off searching a variety of sources and databases - Simbad, NED, SkyBot etc - until it finds the object you are looking for. It then returns the position and some basic information including links back to the original data source.

Over time I've added some bells and whistles to help correct spellings ("Did you mean...?") and added thumbnail Digital Sky Survey (DSS) images from Wikisky. One of the things that has bugged me for ages is that solar system objects were never in the DSS thumbnail. That's because the DSS image is a snap-shot at a particular time and Mars, Comet Halley, Vesta etc weren't there at the time. At Science Hack Day I decided to fix this.

With help from Joe Davis, I hacked together a Yahoo YQL request to find the Wikipedia article for the solar system object being searched for. This involved also sending the object type (e.g. "comet", "planet", "moon") otherwise simple searches such as "Juno" tended to return the wrong article. With that sorted, a second YQL request could be done to extract the image from the infobox in the article. This was also a bit tricky as the infobox sometimes contains a few small images.

Today I properly integrated the thumbnail-image-getter into LookUP. That means that the image details (the image and a link back to where it came from) are also accessible if you prefer your results in XML or JSON formats. That brings me onto more image-based goodness that is possible courtesy of the Royal Observatory Greenwich's Astrotag initiative on Flickr. The ROG are encouraging people to add special tags to their astronomical images to make it easy for machines to find them and do things with them. Here is their video introducing astrotags:




Introducing astrotags from Royal Observatory Greenwich on Vimeo.

Astrotags are exactly the sort of thing LookUP can benefit from. Tonight I made use of the YQL table created by Jim O'Donnell for astrotags and some nice CSS to make the first 5 returned images look like Polaroid snaps. I quite like the result. - taken from Astronomy Blog (www.strudel.org.uk/blog/astro/)]]> Mon, 28 Jun 2010 22:42:00 +0100 http://www.strudel.org.uk/blog/astro/000940.shtml Space Loo http://www.strudel.org.uk/blog/astro/000939.shtml Amanda shares a video discussing how astronauts use

the toilet in space. The practice toilets even have the added feature of an "alignment camera" to ensure accurate "docking".

Back in 2006 I was lucky enough to visit the amazing science museum in Tokyo and one of the exhibits was a mock-up of parts of the International Space Station. I was pleased that they'd included the 'little astronauts room' complete with restraints, foot straps and assorted tubes.

ISS toilet
A mockup of a space station toilet. CREDIT: Stuart
Another of the rooms looked like a rather cramped quarters with photographs on the wall and some bedtime reading. Perhaps Soichi Noguchi sleeps somewhere like this.


ISS mockup
ISS mockup CREDIT: Stuart
- taken from Astronomy Blog (www.strudel.org.uk/blog/astro/)]]> Tue, 18 May 2010 23:24:00 +0100 http://www.strudel.org.uk/blog/astro/000939.shtml Moon and Venus http://www.strudel.org.uk/blog/astro/000938.shtml crescent Moon with Venus nearby. The Moon moves fairly quickly though so the two appeared much closer several hours ago as seen from Australia. The Moon was even seen to occult Venus from India and Northern Africa this morning.

Moon and Venus
The Moon and Venus seen on 15 May 2010 CREDIT: Stuart
- taken from Astronomy Blog (www.strudel.org.uk/blog/astro/)]]> Sun, 16 May 2010 12:06:00 +0100 http://www.strudel.org.uk/blog/astro/000938.shtml